Have a strange problem with coolant going missing and would like to know if anyone has any ideas on it.

Basically purchased a 05 Octavia about 4 months ago and have been checking the coolant level regularly. When I have checked it after the engine has cooled down it has always been at the minimum mark until about six weeks ago when it dropped to about 2 mm below the minimum mark on a cold day. A couple of days later (on another cold day) the temperature gauge alarm went off so checked the coolant level and it had dropped to the bottom of the coolant reservior. Topped it up with mixture of coolant and distilled water and everything was fine for a few weeks.

At the begining of last week when we had a very cold spell the coolant dropped again by about a cm each day (which was topped up). This continued until earlier this week - the level stopped dropping when the weather improved (temperatures were above freezing). I have not had to top up the coolant since Tuesday.

There has been lots of white smoke from the exhaust especially when the engine has been warming up. However the engine does not overheat and there is no white mayonase under the oil filler cap suggesting that the head gasket is OK.

Although there is some greasy condensation on the windscreen after driving off (suggesting a heating core issue) there is no damp patch in the pasanger footwell or coolant smell within the car. The heater is working normally as far as I am concerned.

There are no apparent leaks from any of the hoses within the engine compartment having checked it myself and getting a mechanic to look at it using a pressure tester.

A couple of skodas ago, i had coolant loss..took it to the dealers, and .they could easily have said it was a hole, and charged me for it, but they said there was a fault on the radiator, and fixed it under warranty..skoda rule ok

Probably worth getting it to the dealers for them to check the pressure in the system.

I had loss of coolent a couple of times on both my Golf V5 and Audi TT but I just topped it up. Some slight coolent loss isn't uncommon but if it persistantly lgoes down worth getting it checked.

Took it to the dealer who inspected it with pressure testing equiptment. Could not find a leak but suspects it is an EGR valve issue. A replacement part is on order which will arrive net week (Sounds like an expensive job but covered under warrentee).

Is it possible that coolent could leak through the EGR valve?

Nothing to do with the EGR cooler is it?

I've had a coolant leak on mine for the last 9 months and the dealer cannot find it and will do SH|T about it until the pressure test comes up trumps

I think I'll have to try your dealer

Hope the new part sorts things out

I lost some coolant after not locking the top properly. You turn it until you think it is too tight and it clicks shut. Pressurised system so I guess that's where it went....

Sounds Sooooooooooooooooooooooooooooooooo familiar....................mine is a total pita for this.................have had a new short engine, all new hoses, new header, water pump etc and still happening............. it also is an '05 model..... comes off lease in 6 weeks (company hack): been a fab car otherwise................. glad I wasn't paying!!!!!!!!!!!!!!!!!! still doing it: lost 2 litres going from Rugby to Stockton day before yesterday: have got used to carrying 5 litres of water in the boot!!!!